I have an EOS Kiss X4 (Rebel T2?) with Magic Lantern firmware. It uses the same software referenced in the article for MacOS and Windows. On Linux you can use v4l2loopback and gphoto2 but it requires loading an out of tree kernel module.
Same model.
I've bought it in Japan so the model is labeled Kiss X4. Apparently they give it a different name for the product depending on the market: EOS 550D = Rebel T2i = EOS Kiss X4
Software works but you need to pay a recurring subscription (aargh I hate this model) to unlock features your hardware already supports.
I have an old EOS 550D (I think it's called Rebel T2 in the US?) and I can use the webcam software for free. I downloaded a copy back in 2020 when Covid hit and Canon decided to release it. Maybe that would be the key to reverse engineer it and make it free for everybody?